Techniques for allowing a home agent to provide location/presence-based services are provided. In one embodiment, a point of attachment of an access network receives a discovery request from a mobile node. A mobile node is associated with a home agent in a home network different from the access network. Location/presence-based information is determined at the point of attachment. The location/presence-based information is added to a registration request at the layer 3 protocol layer. The registration request is then sent from the point of attachment to the home agent. When the registration request is received at the home agent, the home agent parses the registration request to determine the location/presence information from the request. The home agent then performs a location/presence service using the location/presence information.